mahout-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Andrew Musselman (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (MAHOUT-1349) Clusterdumper/loadTermDictionary crashes when highest index in (sparse) dictionary vector is larger than dictionary vector size?
Date Sat, 07 Dec 2013 19:16:35 GMT

     [ https://issues.apache.org/jira/browse/MAHOUT-1349?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Andrew Musselman updated MAHOUT-1349:
-------------------------------------

    Status: Patch Available  (was: Open)

Added a test, made it pass.

> Clusterdumper/loadTermDictionary crashes when highest index in (sparse) dictionary vector
is larger than dictionary vector size?
> --------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: MAHOUT-1349
>                 URL: https://issues.apache.org/jira/browse/MAHOUT-1349
>             Project: Mahout
>          Issue Type: Bug
>          Components: Integration
>    Affects Versions: 0.8, 0.7
>         Environment: N/A
>            Reporter: Alex Piggott
>            Assignee: Andrew Musselman
>            Priority: Minor
>             Fix For: 0.9
>
>
> I'm not sure if I'm doing something wrong here, or if ClusterDumper does
> not support my (fairly simple) use case
> I had a repository of 500K documents, for which I generated the input
> vectors and a dictionary using some custom code (not seq2sparse etc).
> I hashed the features with max size 5M (because I didn't know how many
> features were in the dataset and wanted to minimize collisions).
> The kmeans ran fine and generate sensible looking results, but when I tried
> to run ClusterDumper I got the following error:
> #bash> bin/mahout clusterdump -dt sequencefile -d
>  completed/5159bba4e4b0718d03c8cf79_/EmailContentAnalytics_dict_5159bba4e4b0718d03c8cf79/part-*
> -i test-kmeans/clusters-19 -b 10 -n 10 -sp 10 -o ~/test-kmeans-out
> Running on hadoop, using /usr/bin/hadoop and HADOOP_CONF_DIR=
> MAHOUT-JOB: /opt/mahout-distribution-0.7/mahout-examples-0.7-job.jar
> 13/05/17 08:26:41 INFO common.AbstractJob: Command line arguments:
> {--dictionary=[completed/5159bba4e4b0718d03c8cf79_/EmailContentAnalytics_dict_5159bba4e4b0718d03c8cf79/part-*],
> --dictionaryType=[sequencefile],
> --distanceMeasure=[org.apache.mahout.common.distance.SquaredEuclideanDistanceMeasure],
> --endPhase=[2147483647], --input=[test-kmeans/clusters-19],
> --numWords=[10], --output=[/usr/share/tomcat6/test-kmeans-out],
> --outputFormat=[TEXT], --samplePoints=[10], --startPhase=[0],
> --substring=[10], --tempDir=[temp]}
> Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 698948
>         at
> org.apache.mahout.clustering.AbstractCluster.formatVector(AbstractCluster.java:350)
>         at
> org.apache.mahout.clustering.AbstractCluster.asFormatString(AbstractCluster.java:306)
>         at
> org.apache.mahout.utils.clustering.ClusterDumperWriter.write(ClusterDumperWriter.java:54)
>         at
> org.apache.mahout.utils.clustering.AbstractClusterWriter.write(AbstractClusterWriter.java:169)
>         at
> org.apache.mahout.utils.clustering.AbstractClusterWriter.write(AbstractClusterWriter.java:156)
>         at
> org.apache.mahout.utils.clustering.ClusterDumper.printClusters(ClusterDumper.java:187)
>         at
> org.apache.mahout.utils.clustering.ClusterDumper.run(ClusterDumper.java:153)
> (...)
> The error is when it tries to access the dictionary for the feature with
> index 698948
> Looking at the dictionary loading code (
> http://grepcode.com/file/repo1.maven.org/maven2/org.apache.mahout/mahout-integration/0.7/org/apache/mahout/utils/vectors/VectorHelper.java#VectorHelper.loadTermDictionary%28java.io.File%29
> -  checked 0.8 and it hasn't changed)
> It looks like the dictionary array is sized for the number of unique
> keywords, not the highest index:
>   OpenObjectIntHashMap dict = new OpenObjectIntHashMap();
> //...
>   String [] dictionary = new String[dict.size()];
> After I ran my custom dictionary/feature generation code I discovered I
> only had 517,327 unique features, therefore it is not surprising it would
> die on an index >= 517327 (though I don't understand why it didn't die when trying
to load the dictionary file)
> Is there any reason why the VectorHelper code should not create a
> dictionary array that has size the highest index read from the dictionary
> sequence file (which can be easily calculated during the preceding loop)?
> Or am I misunderstanding something?
> It worked fine when I reduced the hash size to be <= than the total number
> of features, but this is not desirable in general (for me) since I don't
> know the number of features before I run the job (and if I guess too high
> then ClusterDumper crashes)
> Alex Piggott
> IKANOW



--
This message was sent by Atlassian JIRA
(v6.1#6144)

Mime
View raw message